The Representation of Spatial Structure in Spoken and Signed Language: A Neural Model

Linguistic research to date has determined many of the factors that structure the spatial schemas found across spoken languages. It is now feasible to determine the comprehensive system that these factors constitute. Among its features, this system has a relatively closed, universally available inventory of fundamental spatial elements that are combined to form whole schemas; it has a relatively closed set of categories that these elements appear in; and it, therefore, has a relatively closed, small number of particular elements in each category of spatial distinctions that each category can ever mark. By contrast, the structural representation of space in signed language systematically differs from that in spoken language in the direction of what appear to be the structural characteristics of scene parsing in visual perception. Among such differences, signed language can mark finer spatial distinctions with its greater inventory of structural elements, categories, and elements per category. It represents many more of these distinctions in any particular expression. It also represents these distinctions independently in the expression, not bundled together into “pre-packaged” schemas. And its spatial representations are largely iconic with visible spatial characteristics. The findings suggest that instead of some discrete whole-language module, spoken language and signed language are both based on some more limited core linguistic system that then connects with different further subsystems for the full functioning of the two different language modalities. The different behaviors of the two language modalities are plausible, given the apparently different intrinsic properties of the neural systems underlying them.